According to The Asahi Shimbun, Dai Nippon Printing Co. said it has developed a film for windows that can double the brightness of a room using natural light while reducing electricity usage by 13 percent.
The film, which is 350 micrometres thick, will go on sale for more than 10,000 yen (US$82) per square meter in January for houses undergoing renovations and offices.
Fine bumps on the film’s interior reflect sunlight to the ceiling, which then disperses the light around the room, according to a DNP official.
DNP researchers conducted experiments after placing the film on the interior side of windows facing north that do not get much sunlight.
They found that the film created twice as much brightness of the rooms. Checking measurements from lighting equipment that automatically adjusts the brightness of rooms, the researchers found the film slashed electricity usage by 13 percent.
The surface of the film is hard, smooth and stain-resistant, making it easy to clean, the company said.
DNP used its technology for anti-reflection film for display screens and other products to develop the window film.
The company is advising customers to let professionals install the film.